[Haskell-cafe] ANNOUNCE: HList-0.3

adam vogt vogt.adam at gmail.com
Fri Nov 1 21:43:34 UTC 2013


We are pleased to announce HList-0.3. This is an update the
well-known library for strongly typed heterogenous lists,
records, type-indexed products (TIP) and co-products. Some
of the highlights are:

 * works with lens. See examples/labelable.hs

 * modern features such as TypeFamilies, DataKinds (Symbol),
   ConstraintKinds, PolyKinds, QuasiQuotes

 * Data instances for HList and Record. One application is
   given in examples/cmdargs.hs

 * named and optional function parameters (using
   Keyword or perhaps RecordPuns) are part of the library

 * additional functions including: HTranspose, HZip,
                                   HFoldl, HScanr,

 * improved type inference. To give an example:

    > let y = hMap (Fun' read :: Fun' Read String) x

   This is about the same as `let y = map read x', but
   each element of the HList `y' can have a different
   type. Only one of the two lengths needs to be specified.

 * more documentation and examples, which should make it
   easier to find your way around.

Refer to the included ChangeLog or `darcs changes` for more

This release requires ghc>=7.6. You can get the release from
<http://hackage.haskell.org/package/HList> or use cabal-install:

 $ cabal update
 $ cabal install HList-0.3

For now it seems that hackage is rejecting the upload due to
language extensions it doesn't know about, so in the meantime
you can get it with:

 $ cabal install http://code.haskell.org/~aavogt/HList/HList-0.3.0.tar.gz

With haddocks at <http://code.haskell.org/~aavogt/HList/docs/HList/>.


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